The present invention relates to an optical coupling element and a method for manufacturing the same.
An optical coupling element is configured by, for example, covering a light emitting element and a light receiving element with a light transparent resin and further covering the light transparent resin with a light reflection resin (For example, Patent Document 1).
In this type of optical coupling element, a light receiving element having a high S/N ratio may be configured by adding fine powder such as titanium oxide (TiO2) as a reflective material to an outer covering light reflection resin. In other words, by the light reflection resin to which the reflective material is added, not only can light emitted from the light emitting element be effectively trapped in the light transparent resin, but also incoming light coming from a fluorescent lamp or the sun can be reflected and arrival of incoming light to the light receiving element can be suppressed.
Patent Document 2 describes that an S/N ratio of the light receiving element is improved by adding a dye having a certain light shielding property to the outer covering light reflection resin.
Patent Document 3 describes that fillers configured by titanium oxide and carbon are added to the outer covering light reflection resin.